季节性人工河滨湿地甲烷排放

2008年11月—2009年10月在美国俄亥俄州哥伦布市Olentangy河河滨湿地公园中具有14年历史的补偿河流分岔季节性人工湿地中,运用静态箱-气象色谱法测定了季节性人工湿地中甲烷（CH4）时空排放通量。结果表明：1）CH4排放通量非常低,全年的平均值（以CH4-C计）仅为0.09 mg·m-2·h-1;2）CH4排放通量具有明显的季节性变化规律,年周期的CH4排放通量呈单峰型变化规律,6月份出现排放峰值,但CH4排放通量与土壤温度却无显著相关性;3）季节性人工湿地中心区和边缘区域中的CH4排放量分别为0.03（0.06）和0.03（0.12）mg·m-2·h-1,无显著性差异（P〉0.05）。因此,可见通过设计具有既长又浅形状和湿-干-湿交替水文条件的人工湿地,不仅可应用于其他的河流冲积平原的修复,也可在不同的气候和水文条件下检验其生态服务功能。

Methane emissions from seasonal created riverine wetland

In November 2008-October 2009,a field research by the method of static chamber-gas chromatography was conducted on the spatiotemporal pattern of methane（CH4） emission from the created seasonal oxbow in the Wilma H.Schiermerier Olentangy River Wetland Research Park in Columbus,Ohio,USA.The result showed that,methane fluxes from the created oxbow were extremely low,with no more than 0.09 mg CH4-C m-2.h-1.CH4 emission fluxes had obvious seasonal pattern,and the pattern was single-peaked curve.However,CH4emission fluxes and soil temperature had no significant correlation.There was a seasonal pattern of CH4emissions.The CH4 emission rates of open water zone and transition zone of oxbow were 0.03（0.06） and 0.03（0.12） CH4-C m-2.h-1（P〉0.05）.Thus,hydrologic dynamics must be carefully planned in created and restored wetlands.It would be worth replicating this wetland design with in its long and shallow shape and wet-dry-wet pulsing conditions throughout the world＇s river floodplains.